It does not have to work for long.
All real gyro aircraft attitude indicators self erect after
a certain delay.  You don't stay in a turn or dive
forever.

"Most panel mounted gyros use gravity sensitive control vanes porting air
exiting the gyro housing. An electric fan blows air through 4 ports covered or
opened by the control vanes creating the needed balancing torques."

Get a couple of mercury switches out of your thermostat
for a mems based unit :)

Paul Lamar